Mechano-electrical fuse for a hand grenade
Described is a mechano-electrical fuse (10) for a hand grenade (76), which has a spring element for the storage of mechanical energy and which has a drive device connected to the spring element for driving an electrical generator (28) by means of the mechanical energy stored in the spring element. The electrical generator (28) is connected together by way of an electronic delay circuit (56) with a detonator (46), with which a booster charge (48) is associated. A barrier (40) is provided between the detonator (46) and the booster charge (48). The spring element is formed by the tensioning spring (24) associated with the handle lever (18) of the hand grenade (76). The drive device has a taut cable line (68) which is fixed with its one end (70) to the generator shaft (30) and wound with a number of turns (72) around the generator shaft (30). The second end (74) of the cable line (68) is mounted to the handle lever (18). Fixed to the generator shaft (30) is a flywheel mass (32) which is fixed releasably by means of a shearing element (92) in the fuse housing (16) of the mechano-electrical fuse (10).
The invention concerns a mechano-electrical fuse for a hand grenade as set forth in the classifying portion of claim 1.
Such a mechano-electrical fuse for a hand grenade is known from EP 0 781 975 B1. In that known mechano-electrical fuse the spring element provided for storing mechanical energy is formed by a mechanically prestressed coil spring. The handle lever of that known hand grenade is combined in per se known manner with a mechanically stressed tensioning spring. The mechanically stressed coil spring is connected to a drive device for driving an electrical generator. When the safety device for the lever is released, the coil spring is also relieved, in addition to the tensioning spring associated with the lever, whereby the electrical generator is driven. The detonator of the hand grenade is activated by means of the electrical energy produced by the electrical generator. The detonator then fires the booster charge, by means of which the explosive in the hand grenade is fired. A barrier is provided between the detonator and the booster charge in order to prevent unwanted premature firing of the booster charge.
In the case of that known hand grenade material fatigue for the coil spring, which cannot be reliably ruled out, represents a problem. This has an effect on the reliability of that hand grenade.
The object of the invention is to provide a mechano-electrical fuse for a hand grenade, which is of a comparatively simple design and which is of relatively small structural size so that it can also be installed in existing hand grenades without problem.
In accordance with the invention, in a mechano-electrical fuse of the kind set forth in the opening part of this specification, that object is attained by the features of the characterising portion of claim 1. Preferred developments and embodiments of the mechano-electrical fuse according to the invention for a hand grenade are characterised in the appendant claims.
By means of the mechano-electrical fuse according to the invention it is readily possible to satisfy current and future demands from customers, in which respect it is possible for the respectively desired delay times to be adjusted by means of the time delay circuit of the fuse according to the invention - to correspond to the respective national demands prior to fitting of the mechano-electrical fuse in the hand grenade.
Further details, features and advantages will be apparent from the description hereinafter of an embodiment, illustrated in the drawing, of the mechano-electrical fuse according to the invention and a hand grenade having such a mechano-electrical fuse. In the drawing:
Mounted to the housing head 12 is a handle lever 18. The handle lever 18 is displaceable about a lever spindle 20 between the inactive position shown in
Disposed in the fuse housing 16 is an electrical generator 28 which for example can be a microgenerator from Kinetron-bv, 5025 RS Tilburg, Netherlands. The electrical generator 28 has a generator shaft 30 on which a flywheel mass 32 is fixed. The generator shaft 30 is connected by way of a step-down transmission 34 to a barrier displacement shaft 36. A barrier 40 is fixed to the end 38, which is remote from the step-down transmission 34, of the barrier displacement shaft 36. As can be seen from
The electrical generator 28 is connected together with the detonator 46 by way of an electronic, time delay circuit 56. That switching connection is identified by reference 58 in
The time delay of the electronic time delay circuit 56 can be set in a given time window, prior to assembly of the mechano-electrical fuse 10. The time delay can be for example 4.5 to 6 seconds.
The two barrier discs 42 and 44 of the barrier 40 provided between the detonator 46 and the booster charge 48 each have an eccentric through hole 64, 66 (see
A cable line 68 is fixed with its one end 70 to the generator shaft 30. Adjoining that first end 70 a number of turns 72 are wound around the generator shaft 30 in closely contacting relationship. The cable line 68 extends in sealing relationship out of the housing head 12 of the mechano-electrical fuse 10, and it is fixed with its second end 74 to-the lever 18.
In the inactive, safe condition of the mechano-electrical fuse 10 the cable line 68 is provided without slack between the generator shaft 30 and the lever 18, that is to say it is taut.
When the safety device 22 is released from the mechano-electrical fuse 10, the associated tensioning spring 24 can be mechanically relieved. In that situation the lever 18 is pivoted out in
As already mentioned the electronic time delay circuit 56 can be preset for example with a time delay of 4.5 to 6 seconds. In comparison the barrier 40 is armed for example after 3 seconds after release of the safety device 22, thus affording a reliably effective mechano-electrical fuse 10.
Reference 80 identifies a fragmentation casing of the hand grenade 76.
The hand grenade 76 has a lower housing portion 82 and an upper housing portion 84 which are connected together. The upper housing portion 84 usually has an upwardly open central portion 86 in which the mechano-electrical fuse 10 is arranged. The space 88 which remains in the central portion 86 in front of the booster charge 48 can be equipped with a further charge 90.
Identical details are denoted in FIGS., 1, 2 and 3 by the same respective references so that there is no need for all features to be described in detail again with reference to the Figures.
List of references
10 mechano-electrical fuse
12 housing head (of 16)
14 housing sleeve (of 16)
16 fuse housing
18 lever (of 10)
20 lever spindle (for 18)
22 safety device (for 16)
24 tensioning spring (between 12 and 18)
26 first end portion (of 24 at 12)
28 electrical generator (in 12)
30 generator shaft (of 28)
32 flywheel mass (at 30)
34 step-down transmission (between 30 and 36)
36 barrier displacement shaft (for 40)
38 end (of 36 for 40)
40 barrier (between 46 and 48)
42 barrier disc (of 40)
44 barrier disc (of 40)
46 detonator (of 10)
48 booster charge (of 10)
50 compartment (in 52 for 46)
52 circuit body (for 56)
54 frame (of 52).
56 electronic time delay circuit (at 54)
58 switching connection (between 56 and 46)
60 circuit body (of 56)
62 circuit body (of 56)
64 through hole (in 42)
66 through hole (in 44)
68 cable line (between 30 and 18)
70 first end (of 68 on 30)
72 turns (at 70 on 30)
74 second end (of 68 at 18)
76 hand grenade
78 explosive (of 76)
80 fragmentation casing (of 76)
82 lower housing portion (of 76)
84 upper housing portion (of 76)
86 central portion (of 84 for 10)
88 space (in front of 48 in 86)
90 charge (in 88)
92 shearing element
Claims
1. A mechano-electrical fuse for a hand grenade (76), comprising a spring element for the storage of mechanical energy, and a drive device connected to the spring element for driving an electrical generator (28) by means of the mechanical energy stored in the spring element, wherein the generator (28) is connected together with a detonator (46) for the activation thereof, with which a booster charge (48) is associated, wherein a barrier (40) is provided between the detonator (46) and the booster charge (48),
- characterised in that
- the spring element is formed by the tensioning spring (24) associated with the handle lever (18) of the hand grenade (76) and the drive device has a cable line (68) which is fixed with its one end (70) to the shaft (30) of the generator (28) and is wound with a number of turns (72) around the generator shaft (30) and which is mounted with its second end (74) remote therefrom to the lever (18), wherein fixed to the generator shaft (30) is a flywheel mass (32) which is fixed releasably in the fuse housing (16) by means of a shearing element (92).
2. A mechano-electrical fuse according to claim 1 characterised in that the electrical generator (28) is connected together with the detonator (46) by way of an electronic time delay circuit (56).
3. A mechano-electrical fuse according to claim 2 characterised in that the time delay of the time delay circuit (56) is adjustable in a given time window.
4. A mechano-electrical fuse according to claim 2 or claim 3 characterised in, that the time delay circuit (56) is provided on a circuit body (52) provided with a compartment (50) in which the detonator (46) is immovably arranged.
5. A mechano-electrical fuse according to claim 4 characterised in that the time delay circuit (56) is provided on two circuit boards (60, 62) and the circuit body (52) has a frame (54) on which the two circuit boards (60, 62) are mounted facing away from each other and spaced from each other.
6. A mechano-electrical fuse according to one of claims 1 to 5 characterised in that the generator shaft (30) is connected by means of a step-down transmission (34) to a barrier displacement shaft (36), the barrier (40) being fixed to the end (38) of the barrier displacement shaft, which is remote from the step-down transmission (34).
7. A mechano-electrical fuse according to claim 6 characterised in that the barrier displacement shaft (36) extends through the circuit body (52) and the detonator compartment (50) between the two circuit boards (60, 62).
8. A mechano-electrical fuse according to claim 6 characterised in that the barrier (40) has at least one barrier disc from which the barrier displacement shaft (36) centrally projects and which has an eccentrically provided through hole which in the armed position of the hand grenade (76) is aligned with the detonator (46).
9. A mechano-electrical fuse according to claim 8 characterised in that the barrier (40) has two barrier layers (42 and 44) of conforming configuration and of differing thicknesses.
10 A mechano-electrical, fuse according to claim 9 characterised in that the barrier disc (42) towards the detonator (46) is of a greater wall thickness than the barrier disc (44) remote from the detonator (46).
Type: Application
Filed: Apr 9, 2004
Publication Date: Jul 14, 2005
Patent Grant number: 7197983
Inventors: Norbert Barth (Nohfelden/Eisen), Michael Hahn (Nurnberg), Dietmar Kugler (Ottensoos), Wolfgang von Entress-Fursteneck (Altdorf/Rasch), Thomas Arm (Nonnweiler), Erwin Wrobel (Pluwig)
Application Number: 10/821,528